MB2543 Datasheet, PDF (3/13 Pages) NXP Semiconductors – Dual octal latched transceivers with dual enable 3-State

Philips Semiconductors Advanced BiCMOS Products
Dual octal latched transceivers with dual enable
(3-State)
Product specification
MB2543
FUNCTIONAL DESCRIPTION
The MB2543 contains two sets of eight
D-type latches, with separate control pins for
each set. Using data flow from A to B as an
example, when the A-to-B Enable (nEAB)
input and the A-to-B Latch Enable (nLEAB)
input are Low the A-to-B path is transparent.
A subsequent Low-to-High transition of the
nLEAB signal puts the A data into the latches
where it is stored and the B outputs no longer
change with the A inputs. With EAB and
nOEAB both Low, the 3-State B output
buffers are active and display the data
present at the outputs of the A latches.
Control of data flow from B to A is similar, but
using the nEBA, nLEBA, and nOEBA inputs.
PIN DESCRIPTION
PIN NUMBER
50, 51, 1, 2, 3, 5, 6, 7,
8, 9, 10, 11, 12, 13, 15, 16
42, 41, 39, 38, 37, 36, 35, 34,
33, 32, 31, 29, 28, 27, 25, 24
47, 46, 20, 21
49, 44, 18, 23
48, 45, 19, 22
4, 17, 30, 43
14, 26, 40, 52
SYMBOL
1A0 – 1A7,
2A0 – 2A7
1B0 – 1B7,
2B0 – 2B7
1OEAB, 1OEBA,
2OEAB, 2OEBA
1EAB, 1EBA,
2EAB, 2EBA
1LEAB, 1LEBA,
2LEAB, 2LEBA
GND
V_CC
NAME AND FUNCTION
Data inputs/outputs
Data inputs/outputs
A to B / B to A Output Enable inputs (active-Low)
A to B / B to A Enable inputs (active-Low)
A to B / B to A Latch Enable inputs (active-Low)
Ground (0V)
Positive supply voltage
FUNCTION TABLE
nOEXX
INPUTS
nEXX
nLEXX
nAx or nBx
OUTPUTS
nBx or nAx
STATUS
H
X
X
X
Z
Disabled
X
H
X
X
Z
Disabled
L
↑
L
h
L
↑
L
l
Z
Z
Disabled + Latch
L
L
↑
h
L
L
↑
l
H
L
Latch + Display
L
L
L
H
L
L
L
L
H
L
Transparent
L
L
H
X
NC
Hold
H=
h=
L=
l=
X=
↑=
NC=
Z=
High voltage level
High voltage level one set-up time prior to the Low-to-High transition of nLEXX or nEXX (XX = AB or BA)
Low voltage level
Low voltage level one set-up time prior to the Low-to-High transition of nLEXX or nEXX (XX = AB or BA)
Don’t care
Low-to-High transition of nLEXX or nEXX (XX = AB or BA)
No change
High impedance or “off” state
August 23, 1993
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